The proposed research is designed to establish a firmer foundation for the use of NMR spectra to probe stereochemistry for chelates of certain paramagnetic transition metal ions, notably nickel (II), copper(II), and manganese (II). C13 NMR and H1 NMR will be utilized to gain insight into the conformational and configurational features of metal chelates. The Fourier transform NMR technique (FFTNMR) will be used to enhance the poor signal-to-noise ratio usually obtained in studies of this type. Contact shift NMR is extended in this proposal to increase fundamental knowledge of these phenomena in order that stereochemical information can be extracted from observed spectra. The geometrical dependence of contact shifts of NiNCCH and NiXC13C fragments are studied, using simple amino acids, 1,2 - and 1,3-diamine ligands as model compounds. Significant stereochemical studies involving nickel chelates in solution and studies of binding by multidentate amino acid and peptide ligands which do not use all of their potential binding sites are proposed. The characteristics of metal-sulfur bonds such as bond lifetime, rate of sulfur inversion, and conformational preference of alkyl sulfur groups will be studied. Study of the poorly understood coordination by poly-hydroxy acids, such as gulonic acid, is proposed to establish the solution structures. Investigation of the solution structure of manganese (II) and copper (II) chelates using paramagnetic relaxation enhancement is proposed. By measuring T1 for more than one nucleus in the ligand (C13, 1H), a direct measure of the metal ion-nucleus distance and a dimensional map of the complex in solution can be drawn. The nuclear-metal ion distances for carbon and proton atoms obtained from the relaxation enhancement are used in conjunction with known bonding distance of certain molecular fragments to define the disposition of the chelating moiety of simple molecules with application to complicated biological compounds, such as enzymes, envisioned. BIBLIOGRAPHIC REFERENCES: J. F. Desreux and C. N. Reilley, "Evaluation of Contact and Dipolar Contributions to 1H and 13C Paramagnetic NMR Shifts in Axially Symmetric Lanthanide Chelates", J. Am. Chem. Soc., 98, 2105 (1976). C. N. Reilley, B. W. Good, and J. F. Desreux, "A Structure Independent Meth (Text Truncated - Exceeds Capacity)